Password is incorrect.

This product is shipped with the password set as "Password: (None)".
In this case, click [OK] button without entering the password, the setup screen should then be displayed.

If you have set up a password in [Change in an administrator password] in the setup screen, you will need to enter that password in the password field.
Recheck your password and try again.
If you have forgotten your password, refer to [Setting factory default] to restore them to the factory default.

You may have set the password with spaces only while intending to set the password as "No Password". Try entering space as the password. If you cannot logon, refer to the causes described above.